BR102015009910A2 - seamless passenger airbag system. - Google Patents

Abstract

seamless passenger airbag system. Airbag assembly includes a housing having a rail defining an opening. a panel is attached to the rail at a first end and extends over the opening to a second end opposite the first end and raised relative thereto. a substrate overlaps the panel such that the second raised end is closer to the substrate than the first end, and a foam layer extends from the substrate to the panel.

Description

Patent Descriptive Report: "PASSENGER SEAMLESS AIRBAG SYSTEM".

CROSS-RELATED APPLICATION REFERENCE This application claims the benefit of US Provisional Patent Application No. 61 / 989,910 filed May 7, 2014, entitled "PASSENGER-FREE AIRBAG SYSTEM", which is incorporated into this document by reference in its entirety.

FIELD OF THE INVENTION The present invention generally relates to an airbag housing structure including a rail with a sloping lid for a raised leading edge. When used in connection with a soft instrument panel with seamless passenger support systems where foam or the like overlaps with an undesigned support, the lid structure facilitates a reduced thickness of an adjacent portion of the instrument panel over the door. which can reduce and potentially eliminate cases of soft material being thrown toward an occupant during airbag inflation, BmommiQmjimMüàQ [003] Automotive airbag systems include an airbag module mounted inside a housing that is hidden beneath a surface of the airbag. vehicle interior. In particular, passenger airbag systems may include a rail defined by the housing and extending within the associated vehicle dashboard. The rail may be hidden below a dashboard surface or instrument panel substrate. In this type of arrangement, the passenger airbag chute door (which may also be referred to as the chute "roof") extends over an opening of the airbag assembly and is supported by a portion of the housing from a housing. which may include a rail wall.The rail door may be weakened to facilitate tearing when an energy threshold is applied to the underside thereof during airbag activation.The adjacent portion of the dashboard or panel substrate The instrument cluster may include a pre-weakened rupture line that breaks airbag inflation, allowing the airbag to inflate into the rail, out of its opening, and outside the dashboard. [004] In applications where the rail is covered over a portion of the instrument panel, multiple layers may extend over the track door and other areas thereto, such material typically being bonded to both the door and the surrounding portions. s of the instrument panel support structure. These layers may include the visible outer layer of the dashboard as well as the intermediate layers, which may include foam or the like (used by "soft touch" dashboard structures). Some variations of these overlaid arrangements may be "bare" structures. where the outermost layer of the instrument panel is not pre-weakened along any particular predetermined break seam. Depending on the type of material used for the outer layer of the instrument panel, the force required for inflation airbag breakage non-weakened material can be considerably larger than for pre-weakened structures or in arrangements employing weaker materials.In one example, leather instrument panels may require a particularly high level of inflation force. Further advances in airbag rails and related structures are desirable.

SUMMARY OF THE INVENTION According to claim one aspect of the present invention, an airbag assembly includes a housing having a rail defining an opening. A panel is attached to the rail at one first end and extends over the opening to a second end opposite the first end and raised relative thereto. A substrate overlaps the panel such that the second raised end is closer to the substrate than the first end, and a foam layer extends from the substrate to the panel. According to claim another aspect of the present invention, a vehicle instrument panel includes a substrate and an airbag rail underlying the substrate with a panel attached to it at one end and extending thereon for a second far end. The instrument panel further includes a foam layer between the substrate and the panel that tapers from a first thickness over the first panel end to a second thickness over the second panel end, the second thickness being less than 50%. of the first thickness. According to claim another aspect of the present invention, an airbag housing includes a rail having a plurality of walls and defining an opening. A fiange extends out of the gutter and usually surrounds the opening. A panel is coupled to one of the walls at a first end adjacent the fiange and extends over the opening to a second end opposite the first end. The panel defines a slanted section to position the second end at a distance above the fiange. These and other aspects, objects, and features of the present disclosure will be understood and appreciated by those skilled in the art in studying the following report, the claims, and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: [010] FIG. 1 is a perspective view of an interior compartment of an automobile having an airbag module and related instrument panel components. Fig. 2 is a perspective view of the airbag module and adjacent instrument panel components. [012] Fig. 3 is a perspective cross-sectional view taken along line A-A of FIG. 1 of an airbag module and associated instrument panel components in accordance with the present disclosure. [013] Fig. 4 is a detail view of the airbag module and instrument panel components of FIG. 3 illustrating the soft material of reduced thickness. [014] Fig. 5 is a detail view of the airbag module and instrument panel of FIG. 4 at an early stage of airbag inflation. [015] Fig. 6 is a detail view of the airbag module and instrument panel components at a subsequent airbag inflation stage. [016] Fig. 7 is a perspective cross-sectional view of a prior art airbag module. [017] Fig. 8 is a detail view of the prior art airbag module of FIG. 7

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS [018] For the purposes of the description presented in this document, the terms “top,” “bottom,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal, "Interior", "exterior" and derivatives thereof will refer to the invention as directed in Fig. 1. However, it is important to understand that the invention may assume various alternative orientations except where otherwise expressly specified. It will be understood that the specific devices and processes illustrated in the accompanying drawings and described in the following report are simply exemplary embodiments of the inventive concepts defined in the appended claims.Therefore, specific dimensions and other physical characteristics related to the embodiments disclosed herein should not be considered as limiting. unless expressly stated otherwise. unless otherwise specified, it should be understood that discussion of a particular feature or component extending in or along a given direction or the like does not mean that the feature or component follows a straight line or axis in such direction or that it extends only in such direction or in such a plane without other components or directional deviations, unless otherwise specified. [019] Referring now to fig. 1, an interior of a car is illustrated having an airbag housing 10 located next to an instrument panel 12. In the illustrated embodiment, the airbag housing 10 is configured in a "top mount" position, in which the airbag module is adjacent to an upper surface of a dashboard or instrument panel 12. According to another embodiment, the airbag housing 10 could be configured in a "front fastening" position, in which the airbag housing 10 is positioned close to a glove box.

Additionally or alternatively, the car may have an airbag module which may be suitable for use on a steering wheel airbag module 14. The airbag module may be located anywhere on the vehicle in various embodiments. Referring to Figs. 2 and 3, the airbag housing 10 comprises a rail 16 for at least partially enclosing or surrounding an airbag module 8 and a rail door 34 for closing an open top end of the rail 16. The housing 10, as discussed above, it may be positioned within the dashboard 12 or the steering wheel of a vehicle, for example for securing the airbag module 8 therein to a set of two components. The housing 10 also includes a top wall in the form of a movable rail door 34 or door which is positioned within or over an opening 40 of rail 16. A foam layer 18, for example of polyurethane foam or other material polymeric foam extends along a portion of the instrument panel 12 to support and provide a soft feel to the substrate 20 which comprises the outer surface of the instrument panel 12. The foam layer 18 It is positioned such that a portion thereof resides at the top of the chute door 34 of the chute 16, with a remainder of it extending outwardly over the flange 30 and over the internal support structure 13 of the instrument panel 12 (or at least a portion of it). The shapes of the foam layer 18 and the chute door 34 of the chute 16 correspond substantially to the shape of the instrument panel substrate 20. [021] The chute 16 also includes a plurality of walls described as a front wall 24, a rear wall. 26, and two sidewalls 22, 28 extending downwardly from the gutter door 34 (or "gutter roof"). The plurality of walls 22, 24, 26 and 28 together define an interior 38 of rail 16 and surround an opening 40 of rail 16 at an upper end thereof (i.e. adjacent to rail door 34). rear 24, 26 may contain a plurality of window holes 44 for engagement with a corresponding number of attachment hooks (not shown) extending from an airbag module 8. Window holes 44 may have snap tabs 32 which press the hooks inserted to tighten the coupling connections and prevent noise from occurring between the airbag container and airbag rail 16 during vehicle operation prior to inflation of the airbag. As illustrated, the rail door 34 extends over at least a portion of the opening 40 to provide support for the portion of the foam layer 18 and the substrate 20 extending thereon. An outer flange 30 may surround opening 40 and may extend integrally from near the upper end of walls 22, 24, 26 and 28. In addition, rail port 34 may be slightly smaller than opening 40 to provide clearance or during inflation of the airbag (as discussed below) and may be detached from the walls 22, 26, and 28, a hinge portion 36 affixing the rail door 34 to the rail 16 on wall 24 to allow opening of the rail door 34 with relation to rail 16 by flexing it. Alternatively, the rail 16 and the rail door 34 may be of a fully sealed configuration with a tear seam (e.g., a thinned or otherwise weakened boundary area) extending between the rail door 34 and the walls 22 26 and 28. Further, the rail door 34 may be sealed to the rail 16 by a plug (not shown) which is mounted between the rail 16 (i.e., the rail door 34 and the flange 30). and the overlying portion of the foam layer 18. The trough door 34 may also include several holes 44. These holes 44 may be positioned to reduce the mass of the trough door 34 without affecting their supporting or affixing properties. As mentioned above, the hinge 36 extends between one of the walls 22, 24, 26, or 28 of the rail 16 and an edge 46 of the rail door 34 adjacent that wall to provide a flexible affixing to the rail door. rail 34 to rail 16. As shown in FIG. 3, the hinge 36 may extend from a portion of the front wall 24 to join with the rail door 34 continuously extending thereon along one side 42 of the door. rail 34 adjacent the front wall 24. Hinge 36 may be integrally formed of a single piece of material with rail 16 and may further be integrally formed with rail door 34 such that rail 16, rail door 34, and hinge 36 are of a single piece of material, which may be of somewhat flexible material, such as a polymeric material, for example Dexflex ™ or other material that exhibits a ductility level at cold temperatures (at least at -30 ° C) and acceptable hardness aa high temperatures (at least 90 ° C). Other materials such as TPO (Thermoplastic Olefine), TPE (Thermoplastic Esteomer) or TEO (Thermoplastic Esteomer Olefine) can also be used. inflation of the airbag, which may include bending of the hinge 36 as well as adjacent portions of the rail door 34. [024] As shown in figs. 3 and 4, the housing 10 is configured such that a rear edge 46 of the rail door 34 (which is disconnected from adjacent portions of the rail 16) is positioned closer to the substrate 20 than a front edge 42 of the rail door 34. located at the junction (or transition) between trough door 34 and hinge 36. Thus trough door 34 may include a transition, or sloping area 48 to extend in a direction between front edge 42 and raised rear edge 46

Further, the extent reached by the sloped area 48 may be such that the rear edge 46 is positioned at a greater distance from the flange 30 than from the front edge 42, the substrate 20 being spaced a uniformly spacing above the flange 30. In one example , front edge 42 may be positioned generally aligned with flange 30 or spaced above flange 30 by up to 3 mm (+/- 10%). The sloping area 48, which may extend from about 30% to 60% of the total depth of the rail door 34 and may still be positioned adjacent to the rear edge 46, may be such that 0-4 mm of foam lies. at the top of the rail door 34. 1025] A rail extension 50 may extend beyond the flange 30 to meet the raised rear edge 46 and may taper to match the angle of the sloped area 48 along the sidewalls 22 and 28. In a fully sealed variation of housing 10 (as further described above), the rail door 34 may be joined along a tear seam with an upper edge of the rail extension 50 along the sides of the sloped area 48 and In other words, both the rear edge 46 and the rail extension 50 may be positioned beyond the flange 30 to extend closer to the substrate 20 than the remaining portions of the housing 10. [026] Additional style shown 0, the foam layer 18 fills the space between both the instrument panel holder 13 and the outer portions of the housing 10 extending over the airbag module 8 (i.e. the flange 30, the trough door 34 and any other adjacent portions of the housing 10 therebetween). Most of the instrument panel 12, and in particular the area around it housing 10, is configured as a smoothly germinating continuous shape, with the foam layer 18 being of a uniformly germinating thickness below the substrate 20 which it supports. . Foam layer 18 may vary slightly in thickness to compensate for the various features of support 13 or imperfections and transitions thereon. In the prior art example shown in ftgs. 6 and 7, a variation of a rail 116 is shown, wherein the panel 134 extends generally evenly with the fiange 130 and the adjacent portions of the support 113 such that the foam layer 118 is also of a generally uniform thickness. long of him. In the present embodiment of housing 10, shown in figs. 1-6, and with reference to Figs. 3 and 4, in particular, the above-described structure of housing 10 with rail door 34 having an inclined portion 48 to an elevated rear edge 46 adjacent an extension of Rail 50, a Foam layer 18 has reduced thickness in the back edge area 46 and through a transition positioned along a sloping area 48. As shown, substrate 20 is structured to be generally uniform and not to respond significantly (or visually observable) to the presence. sloping area 48 or raised rear edge 46 and extension 50 due to the reduction in the thickness of the foam layer 18, as indicated compared to the baseline thickness of the foam layer in those areas, which is represented by a reference line in the baseline form 52 extending generally perpendicular to the front wall 24. In one embodiment, the rear edge 46 of the rail door 34 may be raised relative to to baseline 52 by about 5 mm (+/- 10%). Such an elevation may result in, for example, a reduction in the thickness of foam layer 18 from about 9 mm (measured, for example, in the area over the fiange 30) to between about 5 mm and about 2 mm in the overlapping area. to edge 46 and track length 50 (all dimensions +/- 10%). In the example shown, the rail length 50 may also be raised above the baseline 52 by about 5 mm to about 10 mm (+/- 10%) and may have a thickness of about 5 mm (+/- - 10%). In another example, the foam layer thickness 18 may decrease by at least about 50% in the rear edge area 46 compared to its thickness over a portion of the tailgate 34 opposite the sloped area 48 from the rear tail 46, as on the front edge 42 and, in another embodiment, between about 50% and about 80%. The rail door 34 (and corresponding portions of the rail extension 50) may be configured to extend generally uniformly with the rear edge 46 (i.e. within generally the same raised position) along a portion 54 between the rear edge 46 and the sloping area 48.

Such a configuration may increase the portion of foam layer 18 that is thinner than portions adjacent it to flange 30, for example. In addition, the angled positioning of the inclined area 48 relative to, for example, the baseline 52 results in a sharpened area 56 of the foam layer 18 extending over an area larger than that of the back edge 46 and the rail extension. 50. In one example, a thinned area 56 of foam layer 18 may be considered a portion of foam layer 18 which is less than 70% thick compared to the thickness of foam layer 18 on front edge 42. In the example shown, the tuned area 56, therefore, may extend over 30% of the area of the gutter door 34 (and in one embodiment over 60%). [029] Foam 18 within the tuned area 56 may reduce the amount of force that the airbag module 8 needs to break the rupture (e.g. by cutting or tearing) the foam layer 18 during airbag inflation compared to other arrangements.

In the prior art example of Figs. 6 and 7, a foam layer 118 is shown having a pre-weakened line 170 along a perimeter portion of the panel 134. This can be achieved, as in the example shown, by a lip 172 extending above the flange 130. for a narrow portion of the foam layer 118. These weakened lines 170 may be a fine-tuned foam line in the foam layer 118 which may be reduced, for example, by 3 mm to 4 mm compared to the remaining thickness of the foam layer 18 to 10. of a width, for example from about 2 mm to 4 mm. The purpose of this type of pre-weakened line 170 may simply be to provide a designated line on which foam layer 118 may be cut (e.g., aligned with the edges of panel 134), without actually providing a significant reduction in force that module 8 needs to actually achieve this cut. This may be due to the fact that many poameric foams, such as a polyurethane, are elastic in nature. This means that the foam will insatiably stretch in plastic deformation to a deforming or breaking force before cutting. The amount of stress required before deformation or rupture is related to the volume of the material, which would include the areas adjacent to a pre-weakened line, as these areas would absorb a portion of the opening force. Therefore, a reduction in the area thickness beyond the desired rupture area, such as the inclusion of the tuned area 56, can reduce the amount of effort required for the foam layer 18 to rupture, as this reduces the overall volume. adjacent to the intended rupture area. Thus, the present housing 10 may provide an arrangement wherein the foam layer 18 may be cut along a perimeter portion of the trough door 34 during airbag inflation by a force of between 5% and 50% less than other layers. foam of a uniform thickness or having a pre-weakened line. In another embodiment, the force reduction may be from about 10% to 20% less, or in another embodiment from 15% to 25% less, or in another embodiment from 30% to 50% less.

Furthermore, by the foam layer 18 tapering from a finer area adjacent the rear edge 46, an additional reduction in breaking strength can be realized along the portions of the foam layer 18 overlapping the sidewalls 22 and 24 of the rail 16. The reduction in shear force for foam layer 18 achieved by incorporating the thinned area 56 may be useful when housing 10 is mounted with an instrument panel 12 having a substrate 20 that is not properly pre-weakened in the foam. trough door area 34. In addition, such housing 10 and the accompanying tuned area 56 of foam layer 18 may result in a lower inflation force requirement or faster inflation times for the airbag module 8 used in a panel. instrument substrate 20 wherein the substrate 20 is leather which may be stronger than other polymers used in the instrument panels or which may be difficult to pre-weaken effectively. Further, reducing the volume of the foam layer 18 in the area surrounding the rear edge 46 may reduce the amount of foam material present and therefore be susceptible to fragmentation. This fragmentation may be caused by pieces of foam material from foam layer 18 separating from it during cutting, which may be undesirable. [032] The movement of trough door 34 during inflation of an airbag is illustrated in figs. 5 and 6. Right after initial inflation of airbag 62 as shown in fig. 5, the forces applied against the underside of the rail door 34 by the inflating airbag 62 may cause the rail port 34, as well as the adjacent portions of the foam layer 18 and the substrate 20 to flex, thereby causing deforming stress on the rail. along the portions of the rail door 34 which are separated from the rail 16. In the example shown, the foam layer 18 experiences deforming stress along a location 58 thereof positioned between the edge 46 of the rail door 34 and the rail extension 50. , which acts through the volume of foam layer 18 extending outward in direction 60 from location 58. As discussed above, the reduction in that volume achieved by incorporating the tuned area 56 may reduce the force required to tension the layer. foam 18, causing her to stretch. As shown in fig. 6, continued inflation of airbag 62 causes foam layer 18 to be tensioned to the breaking point, causing foam layer 18, as well as substrate 20, to tear in the general area of the edges of trough door 34 ( including rear edge 46). The at least partial rupture of the foam layer 18 and the substrate 20 under continued pressure from inflation of the airbag 62 allows the trough door 34 to move at least by rotation away from opening 40. This displacement allows the airbag 62 is deployed towards the passenger. In another embodiment as further described above, the rail gate 34 may also be connected around the remaining portions between rail gate 34 and the wall portions 22, 26, and 28 by a rupturable seal or integrally formed portion therebetween; as discussed above, it may also rupture during airbag inflation to allow the chute door 34 to open and the airbag to open toward the passenger. It will be understood by one of ordinary skill in the art that the construction of the described invention and other components is not limited to any specific material. Other exemplary embodiments of the invention disclosed herein may be formed of a wide variety of materials, unless otherwise described herein. [035] For the purposes of this disclosure, the term "coupled" (in all its forms, pair, coupling, coupled, etc.) generally means the union of two Gomponents (electrical or mechanical) directly or indirectly to one another.

This union may be stationary in nature or removable in nature. This union can be achieved with both components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unit body with one another or with the two components.

This union may be permanent in nature or may be removable or releasable in nature unless otherwise indicated. It is also important to note that the construction and arrangement of the elements of the invention as shown in the exemplary embodiments are illustrative only. While only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art analyzing this disclosure will readily appreciate that many modifications are possible (e.g., variations in size, dimensions, structures, shapes and proportions of various elements, values of parameters, fixation arrangements, use of materials, colors, orientations, etc.) without materially departing from the new teachings and advantages of the recited subject. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown in multiple portions may be integrally formed, the operation of interfaces may be reversed or otherwise altered, the length or width of the structures and / or members or connector or other system elements may change, the nature or number of adjustment positions provided between the elements may change. It is important to note that system elements and / or assemblies may be constructed from any of the wide variety of materials that provide sufficient strength or durability in any of the wide variety of colors, textures and combinations. Therefore, all of these modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the desired exemplary embodiments and others without departing from the spirit of the present innovations. It will be understood that variations and modifications may be made to the above structure without departing from the concepts of the present invention, and furthermore, it will be understood that these concepts are intended to be encompassed by the following claims, unless these claims by their language expressly state the above. contrary.

Claims (20)

Airbag assembly, characterized in that it comprises: a housing including: a rail defining an opening; and a panel joined to the rail at one first end and extending over the opening to a second end opposite the first end and raised relative thereto; a substrate overlapping the panel such that the second end is closer to the substrate than to the first end; and a foam layer extending from the substrate to the panel. Airbag assembly according to claim 1, characterized in that the second end of the panel is raised with respect to the first end being positioned distant from a reference line extending from the first perpendicular end to an adjacent portion of the rail. Airbag assembly according to Claim 1, characterized in that the housing further includes a flange extending out of the rail and surrounding the opening; and the substrate is spaced above the flange at a generally uniform distance. Airbag assembly according to Claim 3, characterized in that the second end of the panel is closer to the substrate than the flange by at least 50%. Airbag assembly according to claim 1, wherein the panel defines an inclined portion toward the second end thereof; and the foam layer defines a tuned portion thereof overlapping the inclined portion of the panel. Airbag assembly according to Claim 5, characterized in that the thin portion of the foam layer extends over the panel. by a distance of from about 30% to about 60% of a total panel distance between the second end and the first end, the tuned portion being adjacent to the second end of the panel. Airbag assembly according to claim 1, characterized in that the housing further includes an extension flange extending between a portion of the rail and the second end of the panel. Airbag assembly according to Claim 1, characterized in that the panel is integrally coupled to the rail by an integral hinge portion, such that the panel is removable with respect to the rail by flexing the integral hinge portion. Airbag assembly according to claim 8, characterized in that: the second end of the panel is disconnected from the rail; and the panel is removable with respect to the rail, such that flexing of the integral hinge portion facilitates movement of the second end of the panel away from the rail. 10. Vehicle instrument panel, characterized in that it comprises; a substrate; an airbag rail underlying the substrate with a panel attached to it at a first end and extending thereon to a second end; and a layer of foam between the substrate and the panel and tapering of a first thickness over the first end of the panel. for a second thickness over the second end of the panel which is less than 50% of the first thickness. Vehicle instrument panel according to claim 10, characterized in that the foam layer tapers from the first thickness to the second thickness over an edge area adjacent to the second end and extends from about 30% to about 10%. 60% of a distance between the first and second panel edges. Vehicle instrument panel according to claim 10, characterized in that: the substrate defines a planar, generally planar external surface of the instrument panel; and the panel defines an inclined area adjacent to the second end thereof such that the panel extends toward the substrate such that the foam layer tapers from the first thickness to the second thickness. Vehicle instrument panel according to claim 10: further comprising a holder, the airbag rail being coupled to the holder and the substrate still overlying the holder; and wherein the foam layer further extends between the substrate and the support at substantially first thickness. Vehicle instrument panel according to Claim 10, characterized in that: The airbag holder and the panel are portions of an airbag housing, the airbag housing further including a flange extending out of the rail and surrounding a her opening; and the substrate is spaced above the flange at a generally uniform distance. Vehicle instrument panel according to claim 10, characterized in that the panel is integrally joined to the rail by an integral pivoting portion, such that the panel is removable with respect to the rail by flexing the integral pivoting portion. Airbag housing, characterized in that it comprises: a rail comprising a plurality of walls and defining an opening; a flange extending out of the gutter and generally surrounding the opening; a panel is coupled to one of the walls at a first end adjacent the flange and extending over the opening to a second end opposite the first end, the panel defining an inclined section to position the second end at a distance above the flange. Airbag housing according to claim 16, The first end being adjacent to the flange being positioned within about 2 mm thereof in a direction perpendicular to the opening; and the distance from the second end above the flange to be at least 5 mm. Airbag housing according to Claim 16, characterized in that the inclined portion of the panel extends from about 30% to about 60% of the total panel distance between the second end and the first end. , the inclined portion being adjacent to the second end of the panel. Airbag housing according to claim 16, characterized in that the housing further includes an extension flange extending between a portion of the rail and the second end of the panel. Airbag housing according to Claim 16, characterized in that the panel is integrally coupled to the rail with an integral hinge portion such that the panel is removable with respect to the rail by flexing the integral hinge portion.